<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <style type="text/css">
      body {
        margin: 0px auto;
        background-color: transparent;
      }
      .loading-wrapper {
        position: absolute;
        top: 50%;
        left: 50%;
        text-align: center;
        transform: translate(-50%, -100%);
      }
      .loading-dot {
        animation: antRotate 1.2s infinite linear;
        transform: rotate(45deg);
        position: relative;
        display: inline-block;
        font-size: 40px;
        width: 40px;
        height: 40px;
        box-sizing: border-box;
      }

      .loading-dot i {
        width: 20px;
        height: 20px;
        position: absolute;
        display: block;
        background-color: #1890ff;
        border-radius: 100%;
        transform: scale(0.75);
        transform-origin: 50% 50%;
        opacity: 0.3;
        animation: antSpinMove 1s infinite linear alternate;
      }

      .loading-dot i:nth-child(1) {
        top: 0;
        left: 0;
      }

      .loading-dot i:nth-child(2) {
        top: 0;
        right: 0;
        -webkit-animation-delay: 0.4s;
        animation-delay: 0.4s;
      }

      .loading-dot i:nth-child(3) {
        right: 0;
        bottom: 0;
        -webkit-animation-delay: 0.8s;
        animation-delay: 0.8s;
      }

      .loading-dot i:nth-child(4) {
        bottom: 0;
        left: 0;
        -webkit-animation-delay: 1.2s;
        animation-delay: 1.2s;
      }

      @keyframes antRotate {
        to {
          -webkit-transform: rotate(405deg);
          transform: rotate(405deg);
        }
      }

      @-webkit-keyframes antRotate {
        to {
          -webkit-transform: rotate(405deg);
          transform: rotate(405deg);
        }
      }

      @keyframes antSpinMove {
        to {
          opacity: 1;
        }
      }

      @-webkit-keyframes antSpinMove {
        to {
          opacity: 1;
        }
      }
    </style>
    <title></title>
  </head>
  <body>
    <div class="loading-wrapper">
      <span class="loading-dot loading-dot-spin">
        <i></i>
        <i></i>
        <i></i>
        <i></i>
      </span>
    </div>
  </body>
</html>
